The prior art discloses fat-soluble vitamin powder compositions which are useful for administration as such and also for the formation of pharmaceutical dosage forms, for example, tablets, capsules, powders, and the like; and for the preparation of animal feeds.
U.S. Pat. No. 2,756,177 discloses a process for preparing dry, free-flowing powders by forming an emulsion containing a vitamin-active material, water, gelatin, and/or gum acacia and a sugar; converting the emulsions to droplets; collecting the individual droplets in a mass of starchy powder in such a manner that the vitamin-active particles formed from the droplets are kept separated from each other until their particulate form is established; and separating the vitamin-active particles from the starchy collecting powder. The vitamin-containing powder prepared according to the above process is water soluble and exhibits satisfactory stability properties for most uses; however, the material does have problems withstanding the stresses of pelletizing when used for the fortification of animal feeds. The vitamin containing material tends to lose its physical integrity under the temperature, moisture, and pressure conditions of the feed pelleting process and results in a loss of the physical integrity of the product thereby compromising the stability of the fat-soluble vitamin.
U.S. Pat. No. 4,670,247 relates to a vitamin-active preparation in the form of a water insoluble beadlet comprising the steps of forming an emulsion containing the vitamin-active material, water, gelatin, and a sugar; converting the emulsion to droplets; collecting the individual droplets in a mass of starchy powder in such a manner that the vitamin-active particles from the droplets are kept separated from each other until their particulate is permanently established; separating the vitamin-active particles from the starchy collecting powder, and heat treating the particles at a temperature of from about 90° C. to about 180° C. In accordance with this process, the heat treatment step insolubilizes the gelatin matrix of the beadlet by a reaction between the carbonyl group of the sugar with the free amino moieties of the gelatin molecule. The resulting beadlets are water-insoluble and exhibit increased stability to the stresses of feed pelleting. The crosslinking process utilizes the ingredients employed in making the beadlet and does not require addition of a crosslinking reagent or additive to the composition.